• ETRI Journal
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• v.28 no.2
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• pp.131-144
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• 2006

This work demonstrates a dead-reckoning (DR) scheme for a low-cost land navigation system and a DR/GPS system design using the sigma point Kalman filter (SPKF). T hrough an observability analysis and some simulations, it is shown that the performances of a stand-alone DR system and DR/GPS system can be improved by employing the proposed DR scheme and SPKF. By using the designed DR scheme and filter, the stand-alone DR system does not have any undetectable errors occurring on the curve trajectory. And the DR/GPS system can provide a stable and seamless navigational solution even in the case where the initial heading estimation error is large, such as 160 degrees, or when the GPS signal is unavailable due to tunnels, buildings, and so on. Simulation results indicate a satisfactory performance of the proposed system.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.4
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• pp.575-582
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• 2013

This paper proposes a map building using the ICP algorithm based robot localization prediction. Proposed method predicts a robot location to dead reckoning, makes a map in the ICP algorithm. Existing method makes a map building and robot position using a sensor value of reference data and current data. In this case, a large interval of the difference of the reference data and the current data is difficult to compensate. The proposed method can map correction through practical experiments.

• Archives of Plastic Surgery
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• v.43 no.1
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• pp.88-92
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• 2016

There are two general categories of lateral osteotomy techniques-the external perforating method and the internal continuous method. Regardless of which technique is used, procedural effectiveness is hampered by limited visualization in the surgical field. Considering this point, we devised a new technique that involves using a wide subperiosteal dissection and internal perforation under direct visualization. Using an intranasal approach, whereby the visibility of the intended fracture line was maintained, enabled a greater degree of control, and in turn, results that were more precise, and thus predictable and reproducible. Traditionally, it has been taken as dogma that the periosteum must be preserved, considering the potential for dead space and bony instability; however, under sufficient visualization of the surgical field with an internal perforating method, complete osteotomy with fully preserved intranasal mucosa could be conducted exactly as intended. This intact mucosal lining compensates for the elevated periosteum. Compressive dressing and drainage through a Silastic angio-needle catheter enabled the elimination of dead space. Therefore, precise, reproducible, and predictable osteotomy minimizing the potential for associated complications such as ecchymosis, that is, bruising owing to hemorrhage, could be performed. In this article, we introduce a novel technique for lateral osteotomy with improved visualization.

• The KSFM Journal of Fluid Machinery
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• v.8 no.3 s.30
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• pp.33-41
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• 2005

The optimum condition is defined as one that best suits the purpose of flocculation; the number of small particles should decrease, while that of large particles should increase. The object of this research was to develop a new impeller and substitute for conventional flocculators. The flow characteristics of turbines and hydrofoil type flocculators in turbulent fluids were observed using a standard $k-{\epsilon}$ Model and a computational fluid dynamics (CFD) simulation program-FLUENT. The experiments were performed to compare PBT(Pitched Blade Turbine) flocculator with twisted hydrofoil type flocculators for velocity distribution, and floe formation at conventional water treatment plants in Korea. As a result of the CED solution, twisted hydrofoil types are similar to hydrofoil flocculators for flow characteristics without regard to the twisted angle, On the other hand, it was established that turbine flocculators are greater than hydrofoil flocculators with flow unevenness and dead zone formation. Twisted hydrofoil type-II (Angle $15{\sim}20^{\circ}$) is the most proper impeller for water flocculation from this point of view with a decreasing the dead zone, maintaining of the equivalent energy distribution and a drawing up of the sedimentation substance from the bottom of the flocculation basin.

• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.267-274
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• 2004

The optimum condition is defined as one that best suits the purpose of flocculation; the number of small particles should decrease, while that of large particles should increase. The object of this research was to develop a new impeller and substitute for conventional flocculators. The flow characteristics of turbines and hydrofoil type flocculators in turbulent fluids were observed using a standard k-$\epsilon$ Model and a computational fluid dynamics (CFD) simulation program- FLUENT The experiments were performed to compare PBT(Pitched Blade Turbine) flocculator with twisted hydrofoil type flocculators for velocity distribution, and floc formation at conventional water treatment plants in Korea. As a result of the CFD solution, twisted hydrofoil types are similar to hydrofoil flocculators for flow characteristics without regard to the twisted angle, On the other hand, it was established that turbine flocculators are greater than hydrofoil flocculators with flow unevenness and dead zone formation. Twisted hydrofoil type- II (Angle $15{\~}20^{\circ}$) is the most proper impeller for water flocculation from this point of view with a decreasing the dead zone, maintaining of the equivalent energy distribution and a drawing up of the sedimentation substance from the bottom of the flocculation basin.

• Journal of Navigation and Port Research
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• v.33 no.2
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• pp.99-104
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• 2009

The Kinematic GPS is well known to provide a quite good accuracy of positioning within an level. Although kinematic GPS assures high precision measurement on the basis of an appreciable distance between a reference station and an observational point, it has measurable distance restriction within 20 km from a reference station on land. Therefore, it is necessary to make out a simple and low-cost method to obtain accurate positioning information without distance restriction In this paper, the velocity integration method to get the precise velocity information of a ship is explained. The experimental results of Zig-zag maneuver and Williamson turn as the ship's maneuvering test, and other experimental results of ship's movement during leaving and entering the port with low speed were shown. From the experimental results, ship's course, speed and position are compared with those obtained by kinematic-GPS, velocity integration method and dead reckoning position using Gyro-compass and Doppler-log.

• Journal of Advanced Navigation Technology
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• v.17 no.6
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• pp.810-815
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• 2013

In case Wi-Fi network based First responder's position tracking system is used, range measurement must be generated from RSSI finger print database. However, it is impossible to build up finger print database and to perform rescue operation at same time in the scene of rescue. In this paper, improvised Wi-Fi network without finger print database and pedestrian dead reckoning based first responders tracking system is proposed.

• Cross-Cultural Studies
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• v.22
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• pp.151-175
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• 2011

In this article, I have analyzed the signification of the death of Don Quijote from the oriental religious and philosophical point of view, comparing with the novels of Kim, DongRi. We are able to read Cervantes' hope for his absolute ideal to be lasting forever via the death of Don Quijote, in the base of a strong will named of Gukyeong's life. In the same time, we can also discovery death as lasting of life in the basis of buddhist idea and death as the unification with nature via the meeting between the living and the dead in the Montesinos Cave. Montesinos Cave symbolizes a unclassified and chaotic space, which the Shamanist can meet the dead with a extatic ceremony and both supernatural life and daily life coexist. Therefore, the symbolic death of Don Quijote in Montesinos Cave is abe to be explained by approaching to absolute freedom named of Hatal, in other words, voluntary and conscious death to escape from the yugo of being. Considering the fact that Kim, Dongri emphasized on the unification of sky, earth and human being, keeping a racial identification in the face of the stream of occidental materialism in the time of Japanese conquest, we can look for the similarity with Cervantes' ideal. Contrary to the religious dogmatic ideal, Cervantes treated to recover the human nature and vitality, transcending the occidental rationalism and religious ideology in the time of Counter-reformation.

• Journal of the Semiconductor & Display Technology
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• v.3 no.1
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• pp.21-26
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• 2004

Recently with the development of power switching device and DSP which has peripheral devices to control AC servo system, the servo technology has met a new development opportunity. Those things make it possible to reduce the time of developing a AC servo system. Fixed point DSP such as TMS320F240x, and TMS320F28x series have a disadvantage in calculating floating number where TMS320C32 or TMS320C31 are floating point DSP. However they usually become a complex hardware system to implement the AC servo system and it increases the cost. In this study, a DSP based AC servo system with a 3-phase PMSM is proposed. The newly produced DSP TMX320F28l2-version C which has the performance of fast speed, 150MIPS, and a rich peripheral interface such as a 12bit high speed AD converter, QEP(Quadrature Encoder Pulse) circuit, PDPINT(Power Drive Protect Interrupt), SVPWM module and dead time module are used. This paper presents a method to overcome fixed point calculating using scaling all parameters. Also space vector pulse width modulation (SVPWM) using off-set voltage and a digital PI control are implemented to the servo system.

• Analytical Science and Technology
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• v.7 no.3
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• pp.329-338
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• 1994

The retention behaviors of natural gas components were studied on a single column by gas chromatography. The dead time, $t_0$ was obtained by using extrapolation of homologous series to determine capacity factors. The plots of retention data for homologous series and carbon number at different temperatures were shown to converge into a single point, which point was determined as a dead time. The results of the effect of temperature on the column efficiency for n-butane exhibited the plate number, N incerased with temperature, but the resolution among the fast eluted components decreased. The adsorption enthalpy (${\Delta}H^0{_{ads}}$) for each component on 28% DC 200 stationary phase was determined, and in order to investigate the retention behaviors of natural gas components the regression analysis of log $t_R$, log k' and log ${\alpha}$ vs. van der Waals volume(Vw), molecular connectivity index(X) and hydrophobic fragmental constant(f) were carred out. Good correlation was found between log k' vs. Vw, and log k' vs. f. The correlations between the physical properties of natural gas and the physical parameters were investigated by the linear regression analysis. The relationships between Vw vs. molecular weight and heating value(${\Delta}H_{comb}$), X vs. boiling point, and f vs. molecular weight, boiling point and heating value exhibited the high correlation coefficient more than 0.99. Using the regression equation between the heating value of natural gas and Vw the predicted heating values from $C_6$ to $C_{10}$ showed good agreement with those reported in the literature within 0.2% relative error.